Nissan Repair: Alternator or blown fuse? 1994 Sentra, advance auto parts, nissan sentra

Question
Hi, I have a 94 Nissan Sentra that is acting like it needs a new alternator, can only start with a jump and dies as soon as battery wears down.  When looking for a new alternator, on the website for "Advance Auto Parts" I found this alert with the alternator I need:(INSTALLATION ALERT! A blown fuse in the lamp circuit may cause a "no charge" condition. Verify that battery voltage is present at the "L" terminal of the alternator plug.; See Tech Tip # 581; Test Chart Page # SP)
Have you heard anything about this?  I can't find out anything else on their site about it and don't know where to check for this possible blown fuse. Also, the alternator is only about a year old, we had to replace it before.Thanks for any help you have

Answer
Barbara,

Yes, this condition can cause the battery to drain as the alternator output will not charge the battery or feed the car.  I would check the output with a multi-meter and see if the alternator has output.  But, it could be the alternator since you probably do like the rest of us and purchase a rebuilt unit.  So, check the output before you replace it.  You can get a multi-meter for $20 bucks at Sears and it is just a matter of touching the black lead to ground and the other lead to the L terminal.  Set the multi-meter on the 20 volt range and it should read between 12 to 14 volts if the alternator is good.